gnw has dthrow chaingrab on Falcon, as well as upthrow chaingrab on FD if you DI away. If you DI up then GnW can just uptilt you for funsies.
if the GnW is patient then it is harder for Falcon to approach, but just dashdance camp and grab and you'll be fine. You have to be just outside of GnW's range in order to punish his moves. If you mindgame him into uptilting then you can grab before he dtilts you and stuff. If he wiffs a dtilt then you can stomp him and destroy his 2D existence with knee.
GnW's bair is just as good as his fair in terms of outprioritizing Falcon's moves. And also, I'm pretty sure GnW can DI out of Falcon's dthrow to avoid his next grab. Not too sure on that though (I don't play many Falcons).
Scar $1 MM GnW vs. Falcon?
@kirbykaze: The reason you don't see GnW dthrow chaingrab is that it is hella hard to do at low percents. You aren't gonna be able to do it on FD (where it is easier because you have uthrow chaingrab as well) is because Fox, Falco and Falcon will probably ban it against you. You have to react perfectly to do it from 0%-50%.